Generally, in a vehicle, a fuel tube forming a fuel line extends between a fuel tank and an engine. The fuel tube includes a fuel pipe made of metal and attached to the fuel tank, and a fuel hose made of a flexible material attached to the engine. The fuel pipe and the fuel hose are connected through a tube connector, such as a quick connector by inserting ends of the fuel pipe and the fuel hose therein.
A coupling clamp is installed to hold two fuel tubes, i.e. a main tube and a return tube, each having the fuel pipe and the fuel hose, to be arranged parallel to each other. Specifically, the coupling clamp holds the two fuel tubes with the tube connectors, each connecting the fuel pipe and the fuel hose, such that the main tube and the return tube are arranged parallel to each other.
For example, as a related art of the coupling clamp, Patent Document 1 discloses a coupling member for holding a pair of fuel tubes to be arranged parallel to each other. The coupling member includes a right side holding member and a left side holding member, each holding the fuel tube, and the right side holding member and the left side holding member are connected through a locking projection part on the right side holding member and a locking hole in the left side holding member.
As another related art of the coupling clamp, Patent Document 2 discloses a clamp for holding a pair of fuel tubes to be arranged parallel to each other. The clamp includes a pair of holding portions, each holding a connector portion of the fuel tube, and the pair of holding portions is connected to each other through an engaging portion extending horizontally from one holding portion and an engaged portion extending horizontally from the other holding portion.